The present invention relates to a multicore fiber, and is preferred to the case where the crosstalk between cores is reduced.
Presently, an optical fiber for use in a popular optical fiber communication system has a structure in which a single core is surrounded by a cladding, an optical signal is propagated through the inside of the core, and information is transmitted.
In the optical fiber communication system in these years, a large number of optical fibers ranging from a few tens to a few hundreds optical fibers are used, and a volume of information transmitted is dramatically increasing. In order to reduce the number of optical fibers in such an optical fiber communication system, such a multicore fiber is proposed in which a plurality of cores is surrounded by a cladding.
For example, Patent Document 1 proposes a multicore fiber in a structure in which a plurality of cores is arranged side by side on a single linear line and these cores are entirely enclosed with a cladding.
[Patent Document 1] JP-A-10-104443